常压电离质谱(AIMS)技术是近20年来质谱研究领域的新兴热点研究方向之一,其重大突破和进展使质谱分析迈向了原位实时、快速高效的新时代。本文以web of science核心数据库文献资料为数据源,利用文献计量学Cite Space和VOS Viewer软件对2...常压电离质谱(AIMS)技术是近20年来质谱研究领域的新兴热点研究方向之一,其重大突破和进展使质谱分析迈向了原位实时、快速高效的新时代。本文以web of science核心数据库文献资料为数据源,利用文献计量学Cite Space和VOS Viewer软件对2000—2024年发表的AIMS相关1180篇文献进行发文量、合作分析、期刊共引及关键词等方面的可视化分析。在此基础上针对其在毒品侦测中的应用,进行研究热点及关键词聚类分析,表明AIMS在毒品缴获物,尤其是新精神活性物质(NPS)的现场侦测、便携式与小型化、快速筛查分析等方面具有突出优势。展开更多
We present n-alkane distributions in the soil samples along a transect from Lhasa on the Tibetan Plateau to Bharatpur in Nepal, which covers a large geographical area and a wide range of climatic conditions. These dat...We present n-alkane distributions in the soil samples along a transect from Lhasa on the Tibetan Plateau to Bharatpur in Nepal, which covers a large geographical area and a wide range of climatic conditions. These data allow us to assess the significance of n-alkane distributions in different vegetation types and their relationships to temperature and precipitation. In the tropical rainforest and broadleaved forest zones, n-alkanes exhibit a bimodal distribution pattern with dominant homologues around n-C_（31） and n-C_（23）. The bimodal distribution of tropical rainforest n-alkanes may be a general pattern because of the presence of many lianas, epiphytic plants, algae and the strong microbial activity and degradation involved in the postdepositional process. In the warm-temperate mixed forest and needle-leaved forest zones, the long-chain alkanes have a pattern of n-C_（31） n-C_（33） n-C_（27）. In the alpine shrub and grassland zone, although the most abundant homologue is n-C_（31） , relatively high n-C_（23） concentrations have also been observed in some samples. The statistical results show a good correlation between n-alkane proxies and climatic factors. The average chain length（ACL） values are positively correlated with precipitation and temperature across the transect. The carbon preference index（CPI） values show a negative correlation with temperature and precipitation along a Lhasa–Bharatpur transect. Although there is a positive relationship between ACL and temperature, it is difficult to separate the two climatic variables（temperature and precipitation） because they are well coupled in the monsoon region.展开更多
文摘常压电离质谱(AIMS)技术是近20年来质谱研究领域的新兴热点研究方向之一,其重大突破和进展使质谱分析迈向了原位实时、快速高效的新时代。本文以web of science核心数据库文献资料为数据源,利用文献计量学Cite Space和VOS Viewer软件对2000—2024年发表的AIMS相关1180篇文献进行发文量、合作分析、期刊共引及关键词等方面的可视化分析。在此基础上针对其在毒品侦测中的应用,进行研究热点及关键词聚类分析,表明AIMS在毒品缴获物,尤其是新精神活性物质(NPS)的现场侦测、便携式与小型化、快速筛查分析等方面具有突出优势。
基金supported by the National Natural Science Foundation of China(Grant nos.41302141 and 41272198)the Geological Research Program of China Geological Survey(No.12120113015400)
文摘We present n-alkane distributions in the soil samples along a transect from Lhasa on the Tibetan Plateau to Bharatpur in Nepal, which covers a large geographical area and a wide range of climatic conditions. These data allow us to assess the significance of n-alkane distributions in different vegetation types and their relationships to temperature and precipitation. In the tropical rainforest and broadleaved forest zones, n-alkanes exhibit a bimodal distribution pattern with dominant homologues around n-C_（31） and n-C_（23）. The bimodal distribution of tropical rainforest n-alkanes may be a general pattern because of the presence of many lianas, epiphytic plants, algae and the strong microbial activity and degradation involved in the postdepositional process. In the warm-temperate mixed forest and needle-leaved forest zones, the long-chain alkanes have a pattern of n-C_（31） n-C_（33） n-C_（27）. In the alpine shrub and grassland zone, although the most abundant homologue is n-C_（31） , relatively high n-C_（23） concentrations have also been observed in some samples. The statistical results show a good correlation between n-alkane proxies and climatic factors. The average chain length（ACL） values are positively correlated with precipitation and temperature across the transect. The carbon preference index（CPI） values show a negative correlation with temperature and precipitation along a Lhasa–Bharatpur transect. Although there is a positive relationship between ACL and temperature, it is difficult to separate the two climatic variables（temperature and precipitation） because they are well coupled in the monsoon region.
